Explosion Proof
SF6 Gas Instrument Transformers
with Silicone Composite Insulators
High-Voltage Instrument Transformers
www.siemens.com/energy
2
Safe and Maintenance-free
Instrument Transformers
Siemens instrument transformers are based on technology from
Trench, one of the global leaders in the field of Instrument
Transformers and now an integral part of Siemens.
With an expertise and experience of all common insulation mediums
like epoxy resin, traditional oil - paper insulation, the SF6 technology
was added to our portfolio and we were the first supplier of gas
insulated voltage transformers for GIS switchgear in 1965.
Due to the excellent experience and overwhelming customer demand
for SF6 gas insulation medium in GIS, this insulation medium was also
applied to Instrument Transformers for outdoor installations.
Since then, our instrument transformers with SF6 insulation have found
world-wide recognition with thousands of units installed all over the
world having broad range of applications and under greatly varying
environmental conditions.
Today, we are a world leader with an entire range of instrument
transformers from 72.5 kV to 800 kV covering:
n
Current transformers
n
Voltage (Potential) transformers
Combined units (Combined Current & Voltage transformers);
n
The factory at Aurangabad fulfills the demand of our customers for
maintenance-free, reliable and explosion-free Instrument Transformers.
3
Insulated for the most extreme conditions
Our design of Instrument Transformers combines the characteristics of the SF6 gas to meet the internal insulation
requirement and a Silicone composite insulator to meet the external insulation requirements, thus offering the
most reliable, safest and EXPLOSION PROOF Instrument Transformers.
Internal Insulation Medium: SF6 gas
n
Permanent constant quality according to IEC 60376
n
No aging of the insulation system - longer lifetime
and minimum risk of failures
n
Self-healing insulation - no insulation impairment
through partial discharges
Non-toxic and non-flammable
n
Re-usable and therefore replacement of insulating
n
material is always possible
Remote and online gas monitoring possible
n
External Insulation: Composite Insulator
flange
n
Shatter Proof Insulator - Explosion Proof
design
interface 1
n
Trouble-free performance in heavily
polluted conditions due to hydrophobic
properties and its transfer to pollution
layers
interface 2
n
Totally maintenance-free - no cleaning or
hot line washing required
n
Lesser creepage distance requirement as
compared to ceramic insulators
n
Easily repairable at site
n
Significant reduction of leakage currents
as well as dry band arcing
n
High mechanical strength of the fiberglass
tube provides earthquake resistance and
resistance against vandalism
4
interface 3
silicone housing
SF6 Instrument Transformers
have been proved.....
...to suit all Environmental Conditions
... to withstand the most aggressive
natural or industrial pollutants
...to operate in all extreme climatic
conditions
...to provide an excellent seismic
withstand capability
...to be the first choice for sensitive sites
e.g. areas with steel and cement
industries, mines and water protection
restrictions
...to give you best Economical
Advantages
...to save cost of routine cleaning of
insulators and periodic testing.
...to avoid shut downs required for
carrying out capacitance and tan delta
measurement tests.
...to save space, foundation support
structures, etc. by using combined
current and voltage transformers
...to guarantee best reliability by using
the non-aging insulation medium - SF6
gas
...to easily change or add cores or
windings even after years of service
(e.g. additional metering cores)
...to meet your Special Requirements
...to save due to lesser leakage currents
...to provide safety for Personnel and
Operation
...to totally avoid any explosion or fire
caused by internal flashover or any other
failure
...to be the safest kind of high voltage
instrument transformer even for
installations at frequented sites
...to avoid Ferro resonance in sensitive
networks
...to work on highest voltage levels
(800kV)
...to use customer designed insulators
with a large variety of numbers and
shapes of the silicone sheds
...to be increasingly used as an
independent small power transformer for
users situated beyond all low voltage
networks
...to have self monitoring system –
density monitor contacts can be wired up
to control room for real time
annunciation
5
Voltage Transformer
Type SVS
Current Transformer
Type SAS
Available from 72.5 to 800 kV
n
Available from 72.5 to 800 kV
n
Single high voltage coil design upto 800 kV ensures
n
measurement accuracy
Low reactance bar type primary conductor provides
n
optimal short-circuit performance
Suitable for line-discharging
n
Perfect transient response
n
Ideal for power plants for tariff metering as accuracy does
n
not depend on the system frequency
Well supported core housing avoids undue stress due to
n
core weights on primary winding
Rupture Disc at the top makes it explosion proof
n
Rupture Disc at the top makes it explosion proof
n
Possibility of remote monitoring of insulation
n
No fire risk
n
Completely maintenance-free PT
n
Possibility of remote monitoring of insulation
n
Freedom from capacitance and tan delta measurement
n
Completely maintenance-free CT
n
6
Combined Transformers
Type SVAS
1
Rupture Disc
2
HV Winding
3
Magnetic Core
4
Spacer
5
Primary Conductor
6
CT Cores
7
Head Housing
8
Outlet Tube
9
Capacitive Grading *
10
Silicone Composite Insulator
11 Terminal Box
Available from 72.5 to 800 kV
n
All types of Current, Voltage and Combined
Transformers are available for all insulation
levels and meet the metering and protection
classes according to international standards
(IEC 60044).
Single high voltage coil design upto 800 kV ensures measurement
n
accuracy
Provides the advantages of a current and inductive voltage
n
transformer at a competitive price
Less foundation space required results in significant reduction in
n
overall switchyard cost
Note: *Not required for 245 kV and
below rated Current Transformer
Savings in handling, installation and maintenance cost
n
Highest System
voltage kV (r.m.s)
Rated Power Frequency
withstand voltage kV (r.m.s)
Rated Lightning Impulse
withstand voltage kV (peak)
Rated Swithching Impulse
withstand voltage kV (peak)
72.5
140
325
--
123
230
550
--
145
275
650
–
170
325
750
--
245
460
1050
--
300
460
1050
850
362
510
1175
950
420
630
1425
1050
525
680
1550
1175
765
975
2100
1550
7
For more information, please contact:
Western Region:
Eastern Region:
Northern Region:
Southern Region:
Mumbai office:
Thane Belapur Road,
Thane - 400 601
Tel.: (022) 2762 3990
Fax: (022) 2762 8002
Kolkata office:
43, Shanti Palli
Rasbihari Bypass Connector
Kolkata - 700 042
Tel.: (033) 2444 9302
Fax: (033) 2444 9012
Delhi office:
Plot No. 6-A, Sector 18
Maruti Industrial Area
HUDA, Gurgaon - 122 015
Tel.: (0124) 284 6000
Fax: (0124) 284 6061
Chennai office:
144, Mahatma Gandhi Road
P. O. Box No. 3323
Chennai - 600 034
Tel.: (044) 2833 4144
Fax: (044) 2833 4450
Vadodara office:
Ohm Business Park
Ellora Park, Subhanpura
Vadodara - 390 023
Tel.: 0265-6692 100
Fax: 0265-6692 190
Siemens Ltd.
Energy Transmission
Instrument Transformers
Aurangabad Works:
E76 – MIDC Waluj,
Aurangabad, India. 431 136
Tel: +91 240 2565 191
Fax: +91 240 2554 701
Order No.: PTD-03-152-045
“Product development is a continuous process. Consequently the data indicated in this
leaflet is subject to change without prior notice. For latest issue contact our Sales Office.”